Jointed rod

ABSTRACT

The present invention is a spinal fixation device that includes an occipital rod having a first end and a second end, and a spinal rod extending from a connection housing having a first end and a second end. The first end of the spinal rod is integral with a portion of the connection housing and the connection housing is configured with an elongated opening, a rotating plug, and a locking mechanism. The elongated opening is configured for mating with the first end of the occipital plate and the locking mechanism is adapted to enable the occipital rod to be locked in a fixed position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application which claims priority toU.S. patent application Ser. No. 13/083,267, filed Apr. 8, 2011, whichis a non-provisional application that claims priority to provisionalapplication Ser. No. 61/322,023 filed on Apr. 8, 2010, each of which ishereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure generally relates to a fixation device forpositioning and immobilizing at least two adjacent vertebrae.

BACKGROUND

Bones and bony structures are susceptible to a variety of weaknessesthat can affect their ability to provide support and structure.Weaknesses in bony structures may have many causes, includingdegenerative diseases, tumors, fractures, and dislocations. Advances inmedicine and engineering have provided doctors with a plurality ofdevices and techniques for alleviating or curing these weaknesses.Typically, weaknesses in the spine are corrected by using devises thatfuse one or more vertebrae together.

One method of correcting the weaknesses in the spine is to use aposterior cervical fixation system that does not only include spinallevel fusion, but can also include fusion to the occipital bone on theback of the skull. In order to connect spinal rods to the occipital boneon the skull from the spinal column, surgeons can either bend straightspinal rods to meet the occipital contours and angles or further bend apre-bent spinal rod, where the spinal rod can be provided in multiplepre-bent angles. However, contouring the spinal rod to meet the desiredangles and contours can be a difficult and time consuming process. Thereis a need for an improved posterior cervical fixation system that can beeasily installed and adjusted.

SUMMARY OF THE INVENTION

The present invention is a spinal fixation device that includes anoccipital rod having a first end and a second end, and a spinal rodextending from a connection housing having a first end and a second end.The first end of the spinal rod is integral with a portion of theconnection housing and the connection housing is configured with anelongated opening, a rotating plug, and a locking mechanism. Theelongated opening is configured for mating with the first end of theoccipital plate and the locking mechanism is adapted to enable theoccipital rod to be locked in a fixed position.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIGS. 1 and 2 are exploded views of a hinged spinal rod system accordingto one embodiment of the present invention.

FIGS. 3 and 4 are views of the assembled hinged spinal rod systemillustrated in FIGS. 1 and 2.

FIG. 5 is a side view of a hinged spinal rod system according to anotherembodiment of the present invention.

FIG. 6 is a top view of the hinged spinal rod system according to thepresent invention.

FIG. 7 is a front view of the hinged spinal rod system according to thepresent invention.

FIGS. 8 and 9 are perspective views of the hinged spinal rod systemaccording to the embodiment illustrated in FIGS. 5-7.

FIGS. 10 and 11 are perspective views of another embodiment of a hingedspinal rod system according to the present invention.

FIGS. 12-16 illustrate yet another embodiment of a hinged spinal rodsystem according to the present invention.

FIGS. 17-19 illustrate yet another embodiment of a hinged spinal rodsystem according to the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The following description of the preferred embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

FIGS. 1-19 illustrate different embodiments of a jointed or hingedspinal rod system that provides various angularly adjustable spinalfixation devices. The systems also provide the flexibility to positionand contour spinal rods to alleviate the majority of complications thatcan arise when trying to complete an occipital fusion. The systemsgenerally include an occipital rod, a spinal rod, a housing having alocking mechanism that couples the occipital rod and the spinal rod in afixed position.

FIGS. 1-4 illustrate a preferred embodiment of a hinged or jointed rodsystem 10. The hinged rod system 10 includes a pivoting occipital rod12, a spinal rod 14 integrated with a housing 16, a locking mechanism18, and a pivoting locking plug 20. The system 10 is configured to allowfor the occipital rod 12 to pivot angularly relative to the spinal rod14 and the housing 16. The occipital rod 12 is an elongated member thatis provided with a first end and a second end. The first end isconfigured to be received within the housing 16. The second end isconfigured to be received within a bone fixation device, such as a bonescrew, a plate, or a hook type device. The spinal rod 16 is alsoprovided with a first end and a second end. The first end of the spinalrod is integral with the housing 16. In one embodiment, the first end ofthe spinal rod 14 can be offset and attached to the housing in differentconfigurations.

The spinal rod 14 may also be contoured and adjusted to pedicle screws,hooks, clamps, bone plates and other such devices to enable fixation ofadjacent vertebrae. The occipital rod 12 and the spinal rod 14 can eachhave any shape or size, and each rod can vary in diameter relative toone another. The rods can also vary in length depending on the indenteduse. In the preferred embodiment, the rods are substantially cylindricalrods.

The housing 16 includes the locking mechanism 18, the pivoting lockingplug 20 and an elongated opening 22. The elongated opening 22 isconfigured to receive the first end of the occipital rod 12 and designedto enable the occipital rod to move 90° in the cephalad-caudal directionwith respect spinal rod 14 and the housing 16. The pivoting locking plug20 is fitted within the housing 16 through an opening 24 and is providedwith an elongated cutout 26. The elongated cutout 26 is positioned sothat it corresponds with the elongated opening 22. Turning to theassembled views of the system 10, as shown in FIGS. 3 and 4, theoccipital rod 12 is laser welded to the pivoting locking plug 22 toprovide additional strength and rigidity to the spinal fixation system.As a result, as the plug is capable of rotating, the spinal rod 12 canalso be pivoted accordingly.

The occipital rod 12 is received within the elongated cutout 26 of thepivoting locking plug 20 and can rotate the length of the elongatedopening 22. The pivoting locking plug 20 pivots and moves with theoccipital rod 12 and provides support for the occipital rod 12 in thehousing 16, thereby reducing any “play” or unnecessary movement withinthe housing 16. The plug also prevents the occipital rod from exitingthe housing through the elongated opening 22.

The system 10 also includes a locking mechanism 18 that is adapted tolock the occipital rod 12 in a fixed position relative to the spinal rod14 and the housing 16. It should be noted that while any technique canbe used to lock the occipital rod 12 in a fixed position, FIGS. 1-4illustrate an exemplary embodiment of a locking mechanism 18. In thisembodiment, the housing 16 is provided with a screw hole 28 which isconfigured to receive a set screw 30. The set screw 30 is used to lockthe pivoting locking plug 20 by compressing upon the outer surface ofthe plug 20 within the housing 16 thereby fixing the occipital rod 12.The locking set screw 30 locks the occipital rod 12 in place once thedesired angulation of the occipital rod 12 with respect to the spinalrod 14 is achieved. The locking set screw 18 is turned until it abutsthe locking plug 20 preventing the locking plug 20 from pivoting orrotating. This, in turn, prevents the occipital rod 12 from pivoting.Although in the preferred embodiment, a locking set screw 30 is used tofasten the pivoting rod to the housing 16, it should be known that anyfastening means that may fix the pivoting rod to the housing 16 may beused. Specifically, in the preferred embodiment, a threaded set screwconfiguration is utilized as a locking mechanism, however, any lockingmechanism such as a pin, a clamp or cam-type system may be applied as acomparable locking mechanism.

Now turning to FIGS. 5-9, another embodiment of the hinged spinal rodsystem 32 is shown. The hinged spinal rod system 32 includes a firstelongated spinal rod 34 and a second elongated spinal rod 36 and aconnecting element 37. The connecting element 37 is comprised of a rodreceiving element 38 and a clamping element 40. The first elongatedspinal rod 34 is received within the connecting element 37 through anopening in the rod receiving element 38 of the connecting element 37.The rod receiving element 38 is also provided with a bushing within theopening which enables the angulation of the first elongated spinal rod34. The second elongated spinal rod 36 is integral with the connectingelement 37. Also, as illustrated in FIGS. 5-9, the rod receiving element38 is integrally connected to the connecting element 37. The clampingelement 40 is provided with a bore that is configured to receive aclamping screw 42. As the clamping screw 42 is tightened, the rodreceiving element 38 is compressed thereby locking the first elongatedspinal rod 34 within the rod receiving element 38. It should be notedthat before the clamping screw 42 is tightened, first elongated spinalrod 34 is angulated to be set in an optimal position. Once the desiredposition of the spinal rod 34 is determined, the clamping screw 42 istightened, thereby locking the first elongated spinal rod 34 into afixed position.

FIGS. 10 and 11 are yet another embodiment of a hinged spinal rod system44 according the present invention. In this embodiment, the hingedspinal rod system 44 includes a first elongated spinal rod 46, aconnecting element 48, and a second elongated spinal rod 49 that isintegral with the connecting element 48. The connecting element 48 isprovided with a clamping element 50 and a rod receiving bore 52. The rodreceiving bore 52 is configured to receive the first elongated spinalrod 46 within a bushing 54. The bushing 54 enables the angulation of thefirst elongated spinal rod 46 within the rod receiving bore 52. Theclamping element 50 is configured to receive a clamping screw 56 whichwhen tightened compresses the bushing 54, thereby fixing the firstelongated spinal 48 into a desired position. It should be noted thatalthough a clamping screw 56 is used to tighten the clamping element 50,any mechanism to tighten the clamp to lock the first elongated spinal 46rod may be used.

FIGS. 12-16 are views of another embodiment of a hinged spinal rodsystem 58 according to the present invention. In this embodiment, thehinged spinal rod system 58 includes an elongated spinal rod 60, and aslotted base rod 62. The elongated spinal rod 60 is configured with afirst portion 64 and a second portion 66. The first portion 64 isconfigured to attach to an occipital plate, a screw, hook and anycomparable fixation device. The second portion 66 of the elongatedspinal rod 60 is provided with a washer 68, and a locking nut 69. Thesecond portion 66 of the elongated rod 60 is configured to couple withthe slotted base rod 62. The elongated rod 60 may be translated withinthe slotted base rod 62 and provides for angulation based on the anatomyand design requirements for the fixation of adjacent vertebrae. Theslotted base rod 62 is configured with a slot portion and an extendedrod portion. The slot portion is configured to receive the secondportion of the elongated spinal rod 60. The extended rod portion isconfigured to couple to a spinal plate, a pedicle screw, hooks, and anyother comparable type spinal device. The elongated spinal rod 60 islocked within the slotted base rod 62 through a threaded portion 66 onthe second portion. The threaded second portion engages with threadslocated within the portion of the base of the slotted base rod 62.

FIGS. 17-19 illustrate yet another embodiment of a hinged spinal rodsystem 70 according to another aspect of the present invention. Thehinged spinal rod system 70 includes an elongated pivoting spinal rod72, a fixed spinal rod 74, and a connecting element 76. The fixed spinalrod 74 is configured with a first end 78 and a second end 80. The firstend 78 is spherical and is adapted to be coupled to the connectedelement 76. The connecting element 76 is adapted to be rotatable andpivotable relative to the second end 80 of the fixed spinal rod 74. Theelongated pivoting spinal rod 72 is also provided with a first end 82and a second end 84. The first end 82 of the pivoting spinal rod iscoupled to the connected element 78. In one embodiment, the first end 82of the pivoting spinal rod 72 is threaded and mates with the internalthreading of the connecting element 76. The second end 84 of thepivoting spinal rod 72 is adapted to be received by an occipital plate,bone screws and other comparable fixation devices.

The fixed spinal rod 74 has a slot to control the angulation of thepivoting spinal rod 72 and minimize the medial-lateral rotation at thetop portion. A surrounding element encloses or surrounds the slot toincrease the overall stability of the construct. Once the pivotingspinal rod 72 is threaded through the fixed spinal rod 74, it isaugmented to prevent it from unthreading. The connecting element 76includes a locking nut 86 that includes a countered bottom surface thatmate with the fixed spinal rod 74. As the locking nut 86 is actuated, itseats itself on the top surface of the fixed spinal rod 74 and puts thepivoting spinal rod 72 under a tensile force.

The hinged rod system 70 enables a titanium rod construct to function asa freely angulating hinge until it is locked with a locking mechanismsuch as the locking nut 86. In a preferred embodiment, the hingedmechanism of the present invention allows for in-situ adjustment of therod construct. As a result, less time may be spent by the surgeon inadjusting and positioning the rod construct on the spine.

While it is apparent that the invention disclosed herein is wellcalculated to fulfill the objects stated above, it will be appreciatedthat numerous modifications and embodiments may be devised by thoseskilled in the art.

1. A surgical method comprising: attaching a spinal rod system to anoccipital bone, the spinal rod system comprising: a first spinal rod; asecond spinal rod; and a connecting element adapted to couple to thefirst and second spinal rod; wherein the connecting element isconfigured for angulation of at least one of the first and second spinalrods.
 2. The method of claim 1, wherein one end of the first spinal rodis coupled to an occipital plate.
 3. The method of claim 1, wherein oneend of the second spinal rod is coupled to a pedicle screw.
 4. Themethod of claim 1, wherein the connecting element comprises a rotatinglocking plug.
 5. The method of claim 1, wherein the connecting elementfurther comprises an elongated opening for receiving the first spinalrod.
 6. The method of claim 4, wherein the connecting element furthercomprises a locking mechanism for locking the first spinal in a fixedposition.
 7. The method of claim 4, wherein the rotating locking plug islaser welded to the first spinal rod.
 8. The method of claim 6, whereinthe locking mechanism is a set screw that when tightened compresses therotating locking plug to fix the position of the first spinal rod. 9.The method of claim 1, wherein the spinal fixation device is made ofpeek.
 10. The method of claim 1, wherein the locking mechanism is aclamp.
 11. A surgical method comprising: attaching a spinal rod systemto an occipital bone, the spinal rod system comprising: an occipital rodhaving a first end and a second end; and a spinal rod extending from aconnection housing having a first end and a second end, the first end ofthe spinal rod being integral with a portion of the connection housing;wherein the connection housing is configured with an elongated opening,a rotating plug, and a locking mechanism, wherein the elongated openingis configured for mating with the first end of the occipital plate andthe locking mechanism being adapted to enable the occipital rod to belocked in a fixed position.
 12. The method of claim 11, wherein thesecond end of the occipital rod is coupled to an occipital plate. 13.The method of claim 11, wherein the second end of the spinal rod iscoupled to a pedicle screw.
 14. The method of claim 11, wherein therotating plug further comprises an opening for mating with the first endof the occipital rod.
 15. The method of claim 14, wherein the rotatingplug is inserted into a bore through a central axis of the connectionhousing.
 16. The method of claim 11, wherein the locking mechanism forlocking the occipital rod in a fixed position comprises a set screwlocking mechanism.
 17. The method of claim 11, wherein the rotating plugis laser welded to the occipital rod.
 18. The method of claim 16,wherein the locking mechanism is a set screw that when tightenedcompresses the locking plug to fix the position of the first spinal rod.19. The method of claim 11, wherein the locking mechanism is a clamp.20. The method of claim 19, wherein the second end of the occipital rodis coupled to an occipital plate.